Cooling function
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Cooling function
Simple description of the function:
Solar heating systems with partial solar heating produce more warm water in the summer than can be
used. This function can be used at night to remove some of the excess energy from the lower section
of the cylinder back into the collector when a critical temperature has been reached in the buffer
cylinder by regulating the speed of circulation. During the day, the system will then not have to be
brought to a standstill as often due to excess temperature.
Input
variable: Output
variable:
Enable cooling function
Correcting variable = Speed stage RPM output
Indication of the RPM control-output
Reference temperature
= Measuring point
that sets off the function
Status switching output,
Indication of the switching output
Maximum temperature reference = Tempera-
ture that sets off the function
Special features:
Generally, the maximum value for the thermostat threshold can be set. This value is defined
as an input variable to make it easy to link it. You only need to enter "source"
User
as the set-
ting value. The user can see it as a common function parameter when it appears in the menu
of the function.
In addition to the output indicated with a set speed, the function module also provides a
switchable output. This output can be used to block other functions during the cooling phase.
The maximum set value does not have a hysteresis that can be set, but rather a switch-on and
a switch-off differential.
Entire menu view:
DES: COOL FUNC
FUNCTION STATUS:
INPUT VARIABLE:
OUTPUT VARIABLE:
TIME WINDOW:
00:00 - 06:00 h
Time window for active cooling
REFERENCE TEMP.:
T.ref.ACT: 65.7 °C
Current cylinder temperature (bottom/return)
T.ref.MAX: 90 °C
Cylinder limit
DIFF.ON: 5.0 K
Cooling active between 12 midnight and 6 a.m. above 95°C
DIFF.OFF: 0.0 K
The cooling function is switched off once the temperature drops
below 90°C
CORRECT.VAR.: 15
The pump runs at speed stage 15
Tests have shown that cooling is also sufficient at the lowest speed stages. We therefore recommend
that you use a speed stage just above circulation standstill. For instance, at the stage 5 the pump only
consumes 10% as much energy.
